A plurality of different assemblies and layer sequences are known in the field of ultrasonic transducer assemblies.
The generic European Patent EP 0 974 814 B1 discloses a coupling element with a support or contact surface, which has a recess for holding a piezoelectric element. A metal disk is arranged between the coupling element and the piezoelectric element. This metal disk is glued onto a plane, which is inclined to the support surface and also forms a base surface of the recess. This design has fundamentally proven itself and is appealing owing to its high thermal cycling. However, occurrence of high impedance differences between the metal disk and the coupling element has been observed.